1 - I agree that this would be nice, but it'd be a lot of work. It's true that the three classes play similarly. There are subtle differences but not all are immediately obvious.
2. I don't like the idea of being aligned with a certain race of creatures. One of the great things about KB is the random nature of it. Aside from morale issues, you can combine anything with anything. Alignment with races would limit that. I'll all in favour of more unit types though.
3. YES! More items would be great, and the ability to forge them would be great too. Only downside is it would reduce the randomness.
4.
NO! Are you insane? Isn't 500+ fights enough for you?
I would hate respawning stacks, as I am a completist who likes to clear everything out.
5. This would be great, but KB isn't really about choices and consequences. It's not really that kind of game. This isn't to say I wouldn't like to see more of this.
In summary, I think you are wanting the game to be a little more streamlined in terms of story. Aligning with a race and wanting more good and evil choices is evidence of this. What I love about KB:TL is the random nature of it. Games play out differently due to this random element, which is great because I've nearly finished it five times now. I would simply like to see more variation - more units, more items, more spells. That would enhance the replayability for me.
The other thing I would dearly love is a screen where you can see which units are available in which locations. A search screen like in Space Rangers 2, basically. You would still have to travel there though. The other thing that would be cool is varying unit prices based on location. This would really influence my decision making and maybe make me use non-optimal units if they were cheap.